Among
eIF4E family members, eIF4E1 plays the central role in mRNA recruitment.
Regulation of cap-dependent translation by
eIF4E inhibitory proteins.
In addition, several proteins involved in translational machinery, like EIF1, EIF3J, and
EIF4E, and different 40S ribosomal proteins are among the underexpressed group of proteins.
Activated MEK-ERK signaling enhances eukaryotic translation initiation factor 4E (
eIF4E) phosphorylation via activated MAPK-interacting protein kinase-1 (MNK1), which may lead to enhancement of P2X4R translation.
This is associated with a redistribution of
eIF4E from an active complex (i.e., eIF4E-eIF4G) to an inactive complex (i.e., eIF4E-4EBP1), thereby preventing mRNA translation.
4EBP1 binds to the translation initiator factor
eIF4E, repressing protein synthesis.
Initiation begins with the assembly of eIF4F complex comprising
eIF4E, eIF4G, and eIF4A onto the 5' [m.sup.7]G cap (Figure 1).
For instance, SGs induced by glucose deprivation contain eukaryotic initiation factor
eIF4E and eIF4G proteins, mRNAs, and the poly(A)-binding protein Pab1 [12,13], whereas SGs induced by oxidative stress have distinct major components such as eIF2 and downstream factors [6].
Consistently, NnV suppressed phosphorylation of S6 and
eIF4E. Despite the inactivation of PI3K-mediated p-Akt (Thr308), mTOR1 inhibition still promotes feedback activation of mTOR2-driven phosphorylation of Akt at Ser473 [32, 33].
MiR-1 protects heart structure and functions against cardiac hypertrophic responses by directly targeting and inhibiting translation of many signaling molecules including eukaryotic initiation factor 4E (
Eif4e), Mef2a, Gata4, and histone deacetylase 6 (HDAC6) [7-9].
eIF4E association with 4E-BP decreases rapidly following fertilization in sea urchin.
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EIF4E is the cap-dependent translation initiation factor to shut off host protein synthesis.